Bathtub & Shower Fiberglass Repair Kit with White Gelcoat

Name: Bathtub & Shower Fiberglass Repair Kit with White Gelcoat
Brand: Boat Suppliers
SKU: SK-BTB001
Price: 59.95 USD
Availability: OutOfStock

Bathtub & Shower Fiberglass Repair Kit with White Gelcoat

SKU:SK-BTB001

$59.95 USD

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A proper structural fix for a cracked, soft, or holed fiberglass tub or shower pan, not a cosmetic paint-over. Most bathtub repair kits are a tiny tube of filler that cracks again in a month because the flexing floor underneath was never reinforced. This kit repairs the tub the way a boatyard repairs a hull: glass and resin for strength, then true white gelcoat that cures hard, glossy, and waterproof.

What is in the kit:

1 Pint Silmar 249 clear polyester laminating resin in a sealed metal can
1 Pint pure white gelcoat with wax in a sealed metal can, cures tack-free to a gloss finish
MEKP hardener for both the resin and the gelcoat
1 yard x 38" of 1.5oz chopped strand mat
1 Quart fumed silica thickener, for filling cracks and chips
Prep & Fair sandpaper 6-pack (120 through 400) plus Finish & Polish 6-pack (600 through 3000) for the full wet-sand to gloss progression
Chip brush, 4 mixing cups, 4 mixing sticks, plastic spreader, nitrile gloves

How the repair works: reinforce the flexing area from above (or below if accessible) with resin and mat, fill the crack with silica-thickened resin, then topcoat with the white gelcoat and wet sand through the grits to blend the gloss into the surrounding tub.

Works on fiberglass and most acrylic-over-fiberglass tubs, shower pans, and utility sinks. Enough material for several cracks or one large soft-spot repair, with a real gloss white finish, not a painted-on patch.

Specifications

Structural resin: Silmar 249 polyester, 1 pint, with MEKP
Topcoat: pure white gelcoat with wax, 1 pint, sands and polishes to a finished surface
Reinforcement: 1.5 oz chopped strand mat
Filler: fumed silica, 1 quart
Abrasives: both packs, 120 through 3000 grit, so you can cut and polish in one kit
Surfaces: fiberglass and gelcoat tubs, shower pans and surrounds. Acrylic and steel tubs need a different repair
Cure: usable the next day, full cure 24 to 48 hours

Includes

Features

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How to use this kit

Structural tub and shower pan repair with a gloss white gelcoat finish. Every kit ships with this same sheet printed and in the box.

Safety: MEKP hardener is corrosive. Wear the gloves and eye protection any time it is open; if it gets in an eye, flush with water for 15 minutes and get medical help. A bathroom is a small closed room, so ventilate hard: open the window, run the exhaust fan, and set a fan blowing air out. Mixed resin heats up as it cures: never cap a mixed cup, and pour leftovers out thin to cure. No smoking or flames, and keep the room ventilated until the smell is gone.

What is in the kit

1 pt Silmar 249 polyester laminating resin, metal canthe structural resin behind the repair
1 MEKP hardener, 2 ozcatalyzes both the resin and the gelcoat
1 pt Pure white gelcoat with wax, metal canthe gloss white finish coat, cures tack-free
1 yd 1.5 oz chopped strand mat, 38 in widethe reinforcement under a crack or soft spot
1 qt Fumed silica thickenerstir into resin to make fairing putty
6 Prep & Fair wet/dry sandpaper120 / 150 / 180 / 240 / 320 / 400 grit
6 Finish & Polish wet/dry sandpaper600 / 800 / 1000 / 1500 / 2500 / 3000 grit
1 / 4 / 4 Chip brush, mixing cups, mixing sticks
1 / 1 pr Plastic spreader, nitrile gloves

You supply: acetone, a bathroom cleaner to strip soap scum, a rotary tool or 80 grit block, a dust mask or respirator, masking tape, plastic sheet and a fan.

Mixing MEKP (resin and gelcoat)

2 oz mix	0.9 mL MEKP (about 18 drops)
4 oz mix	1.8 mL MEKP (about 1/3 tsp)
Full pint	7 mL MEKP (about 1.5 tsp)

That is 1.5 percent for 65 to 85 F. Above 85 F drop to 1 percent; at 60 to 65 F go to 2 percent. Quick field rule: 10 drops per ounce.

Working time is 15 to 20 minutes. Mix small batches you can use right away.

The job, start to finish

1

Clean and grind

Strip soap scum and old caulk residue with a bathroom cleaner, rinse, dry, then wipe with acetone. Nothing bonds to soap film, so this step decides whether the repair lasts. Grind the crack open into a wide shallow V back to solid glass, dish the edges out about 12 times the panel thickness, scuff 2 to 3 inches beyond with 120 grit, and mask off the rest of the tub. On an acrylic-over-fiberglass tub, dab catalyzed resin on a hidden spot under the rim first: styrene can craze bare acrylic.

2

Cut your mat

Before mixing anything, cut chopped strand mat to fill the dished area plus one or two larger pieces to cap it. If you can reach the back of the panel through an access panel or from the basement, cut extra mat to laminate underneath as well. Lay the dry pieces in place to check fit.

3

Laminate the repair

Mix a small batch of resin with MEKP (chart at left). Wet the repair, lay in the mat, and stipple resin through it with the chip brush until it turns translucent, then chase air bubbles to the edges with the spreader. A flexing floor or soft spot wants 2 to 3 layers of mat, and the underside laminated too if you can get to it. Let it cure hard, 2 to 4 hours.

4

Fill and fair

Stir fumed silica into a fresh catalyzed batch until it stands in peaks like peanut butter. Spread it over the patch slightly proud of the surface and work it into the low spots. Once cured, sand fair with 120 through 240 grit until the patch feels flush under your flat palm. A tub shows every ripple in reflected light, so take the extra minute here.

5

Gelcoat and polish

Stir the gelcoat well, catalyze it the same as the resin, and brush on 2 coats about the thickness of a business card, 30 to 45 minutes apart. The wax in it lets the last coat cure tack-free. Next day wet-sand 320 then 400, then run the Finish & Polish pack 600 through 3000 with plenty of water and buff with polishing compound to match the tub's gloss.

Works onFiberglass and gelcoat tubs, shower pans and surrounds, utility sinks, and RV or marine wet baths. Acrylic-over-fiberglass tubs after a hidden-spot test.

Not forCast iron, porcelain-over-steel, one-piece ABS or PVC tub liners, and polyethylene. Polyester resin will not bond to them.

If something goes wrong

Laminate feels tacky

Normal. Clear laminating resin stays tacky on top so the next layer bonds to it. It sands fine once hard underneath.

Nothing hardened

Too little MEKP, or the bathroom is under 60 F. Scrape it off, warm the room, and remix.

It kicked in the cup

Too much MEKP, or it is too hot. Cut back and mix 2 to 4 oz at a time.

Gelcoat stayed sticky

The coat went on too thin for the wax to rise. Add another full coat.

Repair lifted later

Soap film or silicone was left on the surface. Everything must be cleaned back to bare glass.

Let the repair cure a full 24 hours before the tub sees water, and re-caulk only once the gelcoat is hard. Touch-up gelcoat and spare grit packs are at boatsuppliers.com.